As noted in the request for applications, a key aspect of heterogeneity in autism spectrum disorders (ASD) is a relatively high number of clinical interventions that are commonly provided but have limited or even no objective evidence to support implementation. Sensory integration deficit (SID) is a controversial but widely used diagnostic classification in ASD and sensory integration based treatment (SIT) is now routinely provided to children with autism spectrum disorder, but has an extremely limited evidence base. The purpose of this R34 proposal will be to complete developmental analyses in preparation for a relatively large randomized comparison trial examining the effects of commonly implemented sensory integration treatment techniques on communication development in ASD. A total of 40 participants with ASD will be randomly assigned to either a sensory integration (SIT) or pivotal response training (PRT) comparison condition. In addition, pre-and post intervention behavioral and neuro-imaging measures of multi-sensory processing will be gathered and analyzed to determine whether changes in multi-sensory processing are associated with SIT intervention. Two years of support are requested. PUBLIC HEALTH RELEVANCE: Children with autism spectrum disorder (ASD) display severe disruptions in communication and social interaction. There are many unproven treatments thought to improve the skills that are widely implemented. The purpose of this project will be to evaluate whether sensory integration treatment is associated with improvements in communication and social skills in children with ASD.